For all Chess geniuses

[The Almighty]

Scenerio
1. It is White's Turn.
2. Pawn can be promoted to any other piece EXCEPT KING after reaching rear rank.
3. White should Checkmate in ONE move.
All the other rules are same as ordinary chess rules.

Edited December 21, 2016 by The Almighty

[DrP]

Are you sure it's in 1 move? Whatever white promotes to the king can take it (although it would be checkmate the move after with queen to B6 I think). Any checks on the king can be evaded (for 1 move at least)... What am I missing?

[DrKrettin]

Are you sure it's in 1 move? Whatever white promotes to the king can take it (although it would be checkmate the move after with queen to B6 I think). Any checks on the king can be evaded (for 1 move at least)... What am I missing?

 

I'm glad you said that. As far as I can see, the king can always move to B8 and not be in check, regardless of the direction the pawn can move in (which I suspect is a key to the problem)

[The Almighty]

Are you sure it's in 1 move? Whatever white promotes to the king can take it (although it would be checkmate the move after with queen to B6 I think). Any checks on the king can be evaded (for 1 move at least)... What am I missing?

ONE move. Otherwise it is obvious.

[DrP]

but what stops the king moving to B8 after promotion... The promotion must be a red herring otherwise as DrK said the king just takes on B8 or escapes any other check by moving to B8. Best I could do was 2 moves (but then I am crap a chess ).

 

At first I thought it was going to be that puzzle that makes you promote to a knight for check mate... but that has the rook and the pawn 1 square left of where they are now (on D and C7 respectively). So in this case promotion to a knight is pointless, I'd promote it to a queen to force the take then check mate with QB6.

 

On second thoughts, maybe I am just missing something - that knight promotion puzzle is different.

One thing seems clear though - whatever you promote to it can be taken by the king.

Edited December 21, 2016 by DrP

[DrKrettin]

It looks impossible to me. I just can't see how to stop the king moving to B8, no matter what we assume. Even if it's a discovered check if the pawn moves to B6.....

Edited December 21, 2016 by DrKrettin

[DrP]

Yea - I look forward to the solution... I think it is impossible for the same reason DrK does... It's check mate in two after promotion to queen or bish to force the take.... then QB6. What are we missing? Let us know after some others have had a go at it.

[The Almighty]

It looks impossible to me. I just can't see how to stop the king moving to B8, no matter what we assume. Even if it's a discovered check if the pawn moves to B6.....

It is If you stick with MY rules.

[DrKrettin]

I've found a solution for mate in HALF a move

 

The pawn is about to take a piece on A8, which has already been removed from the board. It then becomes a queen - checkmate.

[DrP]

If your rules suggest that the pawn doesn't have to reach the back row to be promoted then just make it a queen where it stays and it is checkmate.... but that isn't chess, lol.

 

Using the rules of chess I still do not see it. Where you wrote - "2)Pawn can be promoted to any other piece except a king" - it did not state it had to reach the rear rank.... so you could just promote it on the spot. I don't like it though because that is semantics and not chess. lol.

[The Almighty]

i

 

If your rules suggest that the pawn doesn't have to reach the back row to be promoted then just make it a queen where it stays and it is checkmate.... but that isn't chess, lol.

 

Using the rules of chess I still do not see it. Where you wrote - "2)Pawn can be promoted to any other piece except a king" - it did not state it had to reach the rear rank.... so you could just promote it on the spot. I don't like it though because that is semantics and not chess. lol.

I edited

[proximity1]

 

Rook to C8.

 

Checkmate.

[DrP]

That is stalemate, not mate.

Unless you can define stalemate as 'mate' I suppose. It's not checkmate though.

Edited December 21, 2016 by DrP

[proximity1]

 

You can explain Black's next legal move then. Please do. As I read the board, C7→C8 is checkmate.

[zapatos]

Promote pawn to black knight.

[DrP]

Ok - Promoting to a black piece will do it (not legal move though) - I wonder if that is the answer...

 

 

C8 gives stalemate as the king is not in check and can not make a legal move. (you cannot move into check)

Edited December 21, 2016 by DrP

[DrKrettin]

You can explain Black's next legal move then. Please do. As I read the board, C7→C8 is checkmate.

 

Of course it isn't. It's not even check.

[zapatos]

The Almighty made a point of saying "If you stick with MY rules", which led me to believe I could take literally his statement that "2. Pawn can be promoted to any other piece EXCEPT KING after reaching rear rank."

[The Almighty]

Ok - Promoting to a black piece will do it (not legal move though) - I wonder if that is the answer...

 

Yes. That was the reason for redefining the promotion rule to limit promotion to same colour.

[proximity1]

Of course!

 

F6 --> F2.

 

<strike> Checkmate.</strike>

 

No, that doesn't do it, either, does it?

 

I agree. DrP is right. There's a stalemate from the C7→C8 move but I don't see a single move by White to checkmate. Two moves, yes, but not one.

 

However, I'm definitely not a chess genius. I'll watch the better players explain.

Edited December 21, 2016 by proximity1

[DrKrettin]

The Almighty made a point of saying "If you stick with MY rules", which led me to believe I could take literally his statement that "2. Pawn can be promoted to any other piece EXCEPT KING after reaching rear rank."

 

So the white pawn promotes to something black, and it's checkmate. But that is just a stupid interpretation of "any piece".

 

Edit: I didn't see he had posted. I still think my half-move solution is better.

Edited December 21, 2016 by DrKrettin

[DrP]

I await The Almighty to confirm... You seem right Zapatos... but I was right too in post10 by taking his statement literally and he had to change it... If he intends it to be by the rules of chess then no... if we are allowed to take it literally then I think you are right.

OK - He has posted already...

Yea - I took 'any piece' to mean within the rules... I don't think you can actually promote to a different colour piece though. lol.

 

Interesting though... got any more?

[DrKrettin]

Of course!

 

F6 --> F2.

 

Checkmate.

 

No - K- A6 or B8

[The Almighty]

I await The Almighty to confirm... You seem right Zapatos... but I was right too in post10 by taking his statement literally and he had to change it... If he intends it to be by the rules of chess then no... if we are allowed to take it literally then I think you are right.

OK - He has posted already...

Yea - I took 'any piece' to mean within the rules... I don't think you can actually promote to a different colour piece though. lol.

 

Interesting though... got any more?

Many

[zapatos]

 

So the white pawn promotes to something black, and it's checkmate. But that is just a stupid interpretation of "any piece".

 

 

It wasn't in the "Chess" section of this forum, it was in the "Brain Teasers and Puzzles" section. You have to look for some way in which you are being tricked or misdirected.